Continuous flow reactors comprised of fluidic modules formed of glass or ceramic or similar materials generally involve a significant number of fluidic modules providing elementary functions such as mixing and residence time.
FIGS. 1 and 2 (prior art) are cross sections of an instance of a fluidic module 14 in which can be used. The fluidic module 14 may optionally be comprised of multiple substrates 220, generally at least four as shown at the top of the figure, but more may be included if desired, up to “k” total, as labeled at the left edge of FIG. 1. Between each adjacent pair of the multiple substrates 220, a layer 230 of the module 14 is defined, such that multiple layers 230 are present, generally at least three, and optionally more, with up to k−1 total layers, as labeled at the right edge of FIG. 1. The substrates 220 are joined to each other and supported relative to one another by walls 234 (for ease of viewing, not all labeled), some of which are cut by the cross section of the figure, as indicated by the cross-hatching. Inlet and outlet holes 264, 265 which may extend through one or more of the substrates 220, provide external access to a thermal control fluid path 240 defined in or through one or more of the layers 230, in this case through the two layers 232 of the layers 230. Alternative access routes, such as by holes or gaps (not shown) through walls 234, may be used in place of or in addition to holes 264, if desired.
FIG. 2 is another cross section of the module 14 of FIG. 1, taken in a plane different from but parallel to that of FIG. 1. In the cross section of FIG. 2 may be seen inlet and outlet holes 282, 283 which provide access through substrates 220 to a process fluid path 250 defined through one or more of the layers 230 of the device, in this case through the one layer 231. The process fluid path 250 may include one or more additional inlet ports or holes 282 (in a cross section not shown in FIGS. 1 and 2), such that two or more process fluids can be contacted and/or mixed and/or reacted together within the process fluid path 250. More than one outlet port or hole 283 may also be included on the output end of the process fluid path 250, such that a process fluid may be divided upon exiting the device 210, if desired.
Various materials and methods may be used to form the microstructures 14 or microfluidic devices 210 of the type shown in FIGS. 1 and 2, including methods that produce walls and flat portions or substrates simultaneously as one piece. Methods include, for instance, those disclosed and described in Patent No. EP1964817, entitled “Method for Making Microfluidic Devices and Devices Produced Thereof,” and in Patent Publication No. US2007/0154666, entitled “Powder Injection Molding of Glass and Glass-Ceramics,” and in U.S. Pat. No. 7,007,709, “Microfluidic Device And Manufacture Thereof.”
Where longer residence time or larger capacity is needed, the numbers of layers “k” in a given module 14 may be increased. But it is desirable from design flexibility and cost standpoint to have a few designs of standard modules 14 having fewer layers in each module, and to use such standard modules, linked together, to form any needed reactor configurations. Where standard individual fluidic modules are used, they can be linked together by mechanical connectors employing O-ring seals. Such non-permanent fluidic module stacking still requires seals in between each modules and local compression, presenting additional cost and additional potential leakage points. For reduction of the number of interconnections and for compactness reasons, permanent connection and permanent stacking of individual fluidic modules is desirable.
The present disclosure provides a solution for permanent stacking of fluidic modules practical from both cost and performance standpoints, providing both fluidic sealing and structural support in a single process, resulting in a robust permanently and sealed stack of fluidic modules.